Australia's national security committee will revisit the country's scheduled reopening to students and visa holders in light of the new Covid-19 Omicron strain.
The committee will meet on Monday afternoon to look at whether Australia can reopen to double-dosed visa holders, skilled workers and international students from Wednesday as scheduled.
Federal, state and territory leaders are also expected to meet within the next 24 hours to consider Australia's response.
Prime Minister Scott Morrison has urged calm after the strain was confirmed in two fully vaccinated people travelling from southern Africa who arrived in Sydney over the weekend.
"It is important we just calmly and carefully consider this information, work together, take the decisions that are necessary and that is exactly what everybody is doing," he told the Seven Network on Monday.
Chief Medical Officer Paul Kelly said authorities were looking closely at what Omicron meant for viral transmission and the efficacy of vaccines.
"It does transmit from person-to-person quite readily, at least at well as the Delta virus. And so that means that it will spread," he told ABC television.
"In terms of the vaccines, there is no solid evidence at the moment that there is a problem with that. Although we will wait for further advice and laboratory studies in coming days and weeks."
Agriculture Minister David Littleproud urged people not to panic because the rise of new variants was inevitable.
"We are going to have to open up and we're going to have to learn to live with this and the variants that will come," he told the Nine Network.
"We can't panic. We need to work through this with science, not emotion."
Borders close to nine African countries
Australia has shut its borders to nine southern African countries, while states have brought in new isolation rules for international arrivals.
The South African doctor who alerted authorities to the new variant emphasised the strain did not appear to cause severe illness.
A man in his 30s came to see Angelique Coetzee suffering from fatigue, body aches and pain before he and his family tested positive.
"They were not very sick, none of them were extremely sick," Dr Coetzee said.
"Of course it is concerning, and that is why we're getting all the information we possibly can"
Prime Minister @ScottMorrisonMP says the federal government may scrap allowing visa holders to come to Australia without a travel exemption from December 1 in response to Omicron. pic.twitter.com/oVLZF7Rb31
— Sunrise (@sunriseon7) November 28, 2021
Labor's NDIS spokesman Bill Shorten said the Omicron strain highlighted the need for an effective quarantine system.
"I don't think that 72 hours is enough. And if we don't want to have more severe restrictions, then quarantine is our front-line of defence," he told ABC TV.
Meanwhile, Victoria on Sunday reported 1061 new Covid-19 cases and four more deaths, and NSW 185 additional infections.
There were seven new cases in the ACT and four in the Northern Territory where the remote community of Lajamanu is in lockdown until December 11.
Nearly 87 per cent of Australians aged 16 and older are fully vaccinated.
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